ng the Treaty of 1783 that ended the American Revolution the western-most boundary of the United States was set at the sippi River. Rocky Mountains Pacific Ocean. Appalachian Mountain

## Step 1<br />The question is asking about the western-most boundary of the United States as per the Treaty of 1783, which ended the American Revolution. The options provided are the Mississippi River, the Rocky Mountains, the Pacific Ocean, and the Appalachian Mountains.<br />## Step 2<br />The Treaty of 1783 established the land known as the United States. The western-most boundary of this land was set at the Mississippi River. This is because the Appalachian Mountains were considered the eastern boundary, while the western boundary was the Mississippi River.<br />## Step 3<br />The Rocky Mountains and the Pacific Ocean were not considered the western boundary at that time. Therefore, the correct answer is the Mississippi River.